I believe that my 02 ford explorer is cooling system problem. Noticed car has been hard to start the last few days but ONLY WHEN HOT. I usually watch my gauges regularly and I noticed the coolant temp gauge bounce once or twice then drop. (To the cold end and not move) I thought I might be low on coolant and the ECT sensor wasn't registering. Checked the resevoir and sure enough it was empty. Filled coolant resevoir and started car to see if coolant would get sucked into engine, and see if temp gauge moves. After a short ride to get engine temp up gauge would still not move. But car is experiencing overheating symptoms. Increased idle speed and hard to start when hot. fan clutch seems ok, no leaks in radiator that I can see. No coolant in oil that I can tell. Upper radiator hose gets hot and pressurized. but gauge is still not registering. Does this sound like a thermostat ?

Asked by May 31, 2013 at 02:36 PM about the 2002 Ford Explorer XLT 4WD

Question type: Maintenance & Repair

7 Answers

27,245

If the level was low you probably have air in the system. And for it to be low its gotta be going somewhere

3 of 3 people found this helpful.
18,330

Increased idle speed in normal when the engine is cold. The purpose is to being the engine up to operating temperature. It should automatically slow down after it heats up.

18,330

If there was no coolant in the recovery tank you either have a leak somewhere or the cap on the tank is faulty and will not hold pressure. If the cap does not hold pressure the cooalt will eventually loose pressure. I had the same problem with a 2003. Small loss of coolant over a period of time but no obvious leak. Here is what I did and I discovered the leak. Obtain a radiator pressure tester from Autozone, or the like, and screw on the proper fitting on the recovery tank. Pump the system up to fifteen pounds and let it sit. (cold engine please). Mine was leaking ever so slightly from the thermostat housing (V6) under pressure. The housing is made of plastic (why I do not know) and the metal insert inside the housing goes bad causing a small leak under pressure where the pieces are sandwiched together. The part is about ninty bucks and can be changed by removing the upper radiator hose, the diverter hose to the heater, and three 10 or 8 mm bolts which attached the housing to the top of the manifold. Takes about ten minutes on a cool engine. The termostat comes with the part, so resist the urge to unscrew the cover and look at the thermostat. When under fifteen pounds of pressure the housing leaked like anything. Because of it's location, when it leaks it falls on the manifold then down the block. The leak is so small there was no evidence on the ground because the coolant would evaporate before dripping on the ground.

2 of 2 people found this helpful.
18,330

Correction: If the cap does not hold pressure, the coolant will eventually evaporate out of the system.

1 of 1 people found this helpful.
110,035

Just adding coolant to an empty overflow tank will not always put it back in radiator. Must belch system to insure that radiator and block are full of coolant. Sounds like your system is very low on coolant. Might not show actual engine temp if no coolant is actually making it to temp sensor. Cannot stress enough to double check that block and radiator is completely full.

3 of 3 people found this helpful.
18,330

Dadyoun: How would you belch the system on a 2002 Explorer? The recovery tank is the only place coolant can be added. Inasmuch as the recovery tank is about eight inches above the manifold, gravity and water seeking its level should fill the system almost full. Of course you have to run the engine to get it up to temp so the thermostat will open and begin the flow of coolant back to the radiator.

4 of 4 people found this helpful.
110,035

Sorry was thinking that one had a petcock to release trapped air.

1 of 1 people found this helpful.

Your Answer

Add photo

Related Questions

Explorer

Looking for a Used Explorer in your area?

CarGurus has 72,518 nationwide Explorer listings starting at $1,000.

ZIP:

Search Ford Explorer Questions

Ford Explorer Experts

#1 OJ
OJ
Reputation 10,090
#2 Tom Demyan
Tom Demyan
Reputation 4,110
#3 tennisshoes
tennisshoes
Reputation 2,350
View All

Related Models For Sale

Used Jeep Grand Cherokee
1,023 Great Deals out of 74,887 listings starting at $750
Used Ford Expedition
473 Great Deals out of 24,887 listings starting at $700
Used Chevrolet Tahoe
548 Great Deals out of 29,234 listings starting at $1,699
Used Ford F-150
2,191 Great Deals out of 206,316 listings starting at $1,499
Used Dodge Durango
274 Great Deals out of 22,704 listings starting at $1,200
Used Toyota Highlander
346 Great Deals out of 24,768 listings starting at $2,499
Used Ford Escape
1,391 Great Deals out of 93,563 listings starting at $1,250
Used Toyota 4Runner
249 Great Deals out of 20,494 listings starting at $1,800
Used Honda Pilot
381 Great Deals out of 21,194 listings starting at $1,500
Used Nissan Pathfinder
264 Great Deals out of 22,735 listings starting at $1,995
Used GMC Yukon
374 Great Deals out of 18,226 listings starting at $2,950
Used Ford Explorer Sport
223 listings starting at $4,495

Used Cars For Sale

2016 Ford Explorer XLT 4WD For Sale
88 Great Deals out of 1,569 listings starting at $19,995
2015 Ford Explorer XLT 4WD For Sale
93 Great Deals out of 1,745 listings starting at $16,978
2014 Ford Explorer XLT 4WD For Sale
96 Great Deals out of 2,253 listings starting at $9,990
2013 Ford Explorer XLT 4WD For Sale
25 Great Deals out of 882 listings starting at $12,399

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.